Published March 25, 2005, in the Kirksville Daily Express

Story by Matthew Webber

KIRKSVILLE - The city's water plant supervisor is worried about cryptosporidium - not necessarily because of the Dec. 20, 2004, sale of 427 acres of land in the Hazel Creek Watershed, but because it is his job to worry about cryptosporidium and other contaminants.

"Disinfectants are of little consequence to [cryptosporidium]," Water Plant Supervisor Brian Carter said, regarding the parasite that entered the water supply causing nausea and killing more than 100 people in Milwaukee in 1993, a parasite some citizens have mentioned throughout the recent land-sale process and reacquisition attempt.

"Chlorine won't take it out, because it detects an unfavorable atmosphere, goes into sporulation and therefore can pass through a water treatment plant if filtration is inaccurate," Carter said.

Now some citizens also are worried about cryptosporidium, because the controversial contract for sale does not prohibit cattle on the property, and cattle feces can include the parasite and other contaminants.

99.9 Percent

While city employees and environmental experts agree there may be no 100-percent foolproof method of preventing a large-scale cryptosporidium outbreak or other health epidemic, there are water-treatment methods other than disinfection already in place to help remove "99.9 percent" of cryptosporidium from the local water supply.

"No chemical disinfectant is 100-percent effective," said Everett Baker, Missouri Department of Natural Resources regional head of the public drinking water unit. "The standard for cryptosporidium is 99.9 percent."

However, Kirksville's water treatment plant does meet 100 percent of the state requirements to detect and remove the parasite.

"If they meet these standards, they should be getting these removals, and they are," Baker said. "[The Kirksville water treatment plant] is meeting the standards."

Baker said the state requires water to pass through three stages at water treatment plants: coagulation, stabilization - a stage which Baker describes as almost a repeat of the first, as operators add new chemicals like lime to the water - and then filtration.

These stages are designed to physically remove unwanted particles from water, and "the vast majority of [cryptosporidium] is removed in the first stage of treatment," Baker said.

However, because testing for cryptosporidium itself is "very expensive and very cumbersome" and "you just can't do it continuously," Baker said, water treatment plants rely on surrogate tests like tests of turbidity (or cloudiness) to try to detect the parasite.

Also, the Department of Natural Resources is "monitoring every filter in the water treatment plant continuously" to detect contaminants, Baker said.

The expense of testing is one reason why Baker and the department advocate spending money for water treatment plant upgrades and watershed management plans as better ways of preventing cryptosporidium, Giardia lamblia and other contaminants.

"Lakes are expensive. You want to make them last as long as possible," Baker said. "Expensive updates [to plants] ensure meeting standards. That's money well spent."

The cleaner the initial water source is, Baker added, the easier it will be to treat, and the cleaner the public's drinking water will be.

Hence, Baker applauded the Kirksville City Council's attempt to form a new watershed management commission:

"Hopefully, they'll get a really active committee that will strive to get things done."

Difficult to Clean

Jose Herrera, a biology professor at Truman State University, agreed with the idea of protecting the water supply.

He echoed Baker that more cattle in the watershed or any other changes might take "that much more work to get the water clean," and, the cleaner the water source is, "the less work it's going to take."

"Not that it's uncleanable, but it makes it more difficult," Herrera said.

Although there already are cows in the Hazel Creek Watershed, allowing more cattle possibly could lead to more contamination due to organic material in feces.

"It's not necessarily the cows, but what they're doing, defecating and allowing runoff to run into the water and increase organics in the water," he said.

"We don't really know what kind of pathogens are in there. There might be other viruses, for example."

For the above reasons, Herrera said he opposed the city's land sale, although he has tried not to be involved with the reacquisition attempt.

Also, he hopes he and his students will continue to find clean water when they take samples throughout town as part of a class.

"I'm kind of conscientious about where the water comes from, and in that regard, I'm very much against the sale of land. ...

"I'm concerned enough to err on the side of caution. If you ask anyone, people would prefer water with a buffer."

Regardless of who owns land in the watershed, much of the task of maintaining potable water will fall to the city's water treatment plant and its employees, who will have to remove any new organic material.

"I've talked to Brian [Carter] on a couple of occasions," Herrera said. "I trust what he does. He seems to be doing a good job with what he does."

Flexibility

In addition to the required stages, the supervisor and six water treatment plant operators perform three stages of disinfection with different chlorine compounds to remove particles from the average 2-2.5 million gallons of water per day that enter and leave the plant.

Throughout the 24-hours-a-day, seven-days-a-week process, employees at the 10-acre facility on West Potter Avenue conduct daily, weekly, monthly and yearly tests to monitor water quality and detect any abnormalities as soon as they occur.

These tests, in addition to multiple options among pumps, filters and chemicals throughout the treatment process from which employees can choose, help put several barriers between the original water source and the water that comes out of a tap to protect consumers, Water Plant Supervisor Brian Carter said.

"We have a lot of flexibility in our process if we see that our process isn't working," Carter said.

"That would ensure there's a buffer between the lake itself and the people of Kirksville. We have to have that flexibility to make sure that we always deliver quality water."

This "flexibility" - or "redundancy," in the word of Deputy Public Works Director Jack Schuster - helps operators maintain the city's high water quality, Carter said.

"As the water changes, we can change our process to meet the demands that water is giving us," Carter said.

"So there are a lot of things that ensure in our process that the people are going to get adequate water."

The water passes through a series of filters, clarifiers and mixers before fluoride is added and it leaves the water plant.

Other chemicals like alum, chlorine and carbon are added throughout the process.

From the plant, the water travels into a storage tank and out into the distribution system to faucets, toilets and other water sources in the city limits and some rural areas.

The redundancy in the water treatment process already may have ensured cryptosporidium-free water.

"If there is any out there now, we've been able to handle it thus far," Carter said.

Click here for sidebar, "Water Plant Facts"

Part One: What's in Your Watershed?

Part Two: Clean Water?

Part Three: Where Does Your Water Come From?